Thanks for the response. It definitely is a datura wrightii. Here's a shot of the same plant, a few days later.

HU-64...24, I'm a firm believer in going with the local trends. Zoysia is not a popular choice in PHO for whatever reasons. You can give it a try. There are varieties of all the ones you mention, and they do not all have the same characteristics, so look for zoysia installations and see what you think. In most large cities you can find various grass types in use at places like museums, zoos, and botanical gardens. I am reasonably certain that ASU uses only seeded bermuda, so I can save you the time of looking there. Their stadium grounds are separate from the general university and uses only hybrid bermuda. You can check local nurseries to see if any of them sell zoysia, and ask to see some installations. Check nurseries in/near Scottsdale, because zoysia can be expensive to maintain.

don't forget to fertilize with manganese at least twice a year to prevent "frizzle top". many general palm fertilizers do not include this and it can be bought separate (A&P nursery is where i get mine).

Microclimates are very important here. Much more so than any place I've lived, NY, FL, TX, AK, CA. Unfortunately a pond by itself doesn't really do enough to create a meaningful microclimate. Right next to a water fall does though. Mostly we use shade as the biggest microclimate tool. Unfortunately many kinds of bamboo struggle. They normally survive given enough water but leaves turn brown. Oldhamii does OK in good conditions. Bamboo Ranch in Tucson grows over a 100 kinds but they're a lot cooler, 99-101F avg high in summer while we're 104-107F. If not Bougainvillea then what? It's not a perfect substitute, just as close as I've been able to think of. Pruning will be key though and of course it can't be close to viewers. Moss is a curious plant here. It actually does grow in surprising abundance. Also algae. It's not a great moss, very small, thin layer. It does need shade and overhead watering. Here is some growing on stack of clay brick, horizontal. This was last Sept so still pretty hot. West facing so full sun from say 12-4pm. This grew after some rain but this gets no irrigation. Surprised me. The big difference may be humidity, we get more, 20-40% range, in the fall than spring. Maybe pH? Don't know. The hillside slopes away from the sun but isn't steep enough to shade the soil. But plants and rocks will cast a longer shadow on the soil. I think the key for any moss hope will be overhead watering and not disturbing the soil when weeding, pruning and walking. I've buried wood steps in the hillside for staying off most of the soil. Beyond that I'll just have to try whatever I can. The parts of Japanese, and Chinese for that matter gardens, that interest me in order: 1. Pruned pine trees. I grew up on a fruit farm and learned tree pruning early, but I never learned about pines. I want to see how they react and how they can be controlled. 2. The concept of controlling different views. I've always looked at gardens as art, controlling the view though is new to me and interesting. 3. Using fewer kinds of plants. I've always been a plant collector, trying to jam as many kinds as I could into a space. That was fun, but creating a garden with only a few kinds of plants seems more of a challenge which I like. However the concept of jamming different kinds of gardens, forest, mountain, plains, etc., is kind of the same thing. So still trying to put a lot in a small space. Living in the desert helps me here. The Japanese garden will be almost surrounded by desert garden. The transition I think is interesting. Also, the contrast I hope will help the Japanese areas look more lush. Next a garden in Portland OR it isn't, but next to desert maybe relatively lush. 4. Spend more time in the garden. The current garden I made is desert. It's nice but almost nothing to do. I like working in a garden more than just sitting in a garden. I like weeding, pruning, etc. 5. The challenge of having such a garden in Phoenix. Finding plants that work, creating microclimates for that to happen is fun for me. Like a puzzle. Lots to learn about. 6. How rocks are used. I've built many ponds using lots of rocks but never really thought much about it. Looking at rocks differently now. 7. Use of roof tiles for paths, etc. I'd been doing that for awhile when I found out Japanese had been doing the same thing for a long time. Made me feel like I had a connection to gardeners of hundreds of years ago. Like the way I've come to create gardens is the same way they did. Reuse of what's available. I probably won't be using any lanterns. No raked stone areas, basins, arched bridge, Japanese style fence or other structures or red paint. Thanks for your time.